California Waters - Vol. V | Issue I
In this issue:
- Read about recent studies to help protect fish and waterfowl in California.
- Learn how 6PPD-Q, a byproduct of the tire antiozonant 6PPD, enters Delta water from roadway runoff.
- See new data on the hydrology of the Salinas River Valley.
…Plus, much more!
Scientists Continue Their Study of the Santa Ana Sucker
In the ongoing research of the Santa Ana Sucker (Pantosteus santaanae) USGS scientists try out different sampling methods. The Santa Ana Sucker (SAS) is listed as threatened under the U.S. Endangered Species Act. The Act protects and aims to recover endangered species and their habitats.
California Water Science Center Scientists Share Their Research at 2025 IEP Annual Workshop
From March 4th through the 6th, Scientists from the USGS California Water Science Center presented their research at the at 2025 Interagency Ecological Program (IEP) Workshop in Sacramento. The Interagency Ecological Program (IEP) Workshop is held each spring for sharing new research results that advance science important to IEP and the larger Delta science community.
6PPD-quinone in water from the San Francisco-San Joaquin Delta, California, 2018-2024
The Sacramento-San Joaquin Delta (Delta) is an expansive river delta supplying a large portion of California’s fresh water for agriculture and residential use, and it is also an area of critical habitat for numerous state and federally listed species of concern. In many locations, urban stormwater flows directly into the Delta. 6PPD-quinone (6PPD-Q), an ozonation byproduct of a tire...
New Data on Salinas Valley Hydrology
USGS Scientists evaluate surface water and groundwater resources
Stable Isotopes of Fish, Invertebrates, and Vegetation in the Northern Sacramento-San Joaquin Delta, California, 2022-2024
This dataset includes lab data for stable isotopes of fish tissue, invertebrates, and vegetation collected during daylight hours in the Northern Sacramento-San Joaquin Delta and drainage channels of the Yolo By-Pass, California, USA during summer 2022, 2023, and 2024. This data release includes all animal taxa and isotope values.
Soil Moisture Levels in the Upper Feather River Watershed
Explore real-time soil moisture data by clicking on each point. Access site-specific USGS NWIS Water Data pages for time-series data on soil temperature, electrical conductance, and moisture. Some sites also include NRCS soil profile descriptions.
The anatomy of a drought in the upper San Francisco Estuary: Water quality and lower-trophic responses to multi-year droughts
Multi-year droughts are important and impactful features of California’s Mediterranean climate and can fundamentally affect the water quality and the ecosystem response of the San Francisco Estuary (Estuary) and the Sacramento-San Joaquin Delta (Delta). This study assesses data collected by long-term monitoring programs over the past 46 years (1975-2021) to evaluate how water quality in...
Protecting Protected Land from Pesticides
Five Sacramento National Wildlife Refuges Show Pesticides
The effects of imidacloprid and polyester microfibers on the larval development of the endangered sunflower star
Sea star wasting syndrome (SSWS) has affected numerous species of sea star, with populations of Pycnopodia helianthoides (Brandt, 1835) left most at risk. As their populations are struggling to recover, it is important to gain a better understanding of the impacts that the multiple stressors in their habitats can have on their populations. Contaminant stressors in particular are of...
Geochemical and isotopic data for soils and sediments from the Clear Lake drainage basin, Lake County, California
This dataset includes geochemical, isotopic, and particle-size data for soil and sediment samples collected at approximately 500 sites in the Clear Lake drainage basin, Lake County, California, between November 2021 and December 2023. Data are also reported for ten soil samples collected during October 2018 soon after the Ranch Fire in the upper Scotts Creek watershed. Samples of lakebed...
Updating and recalibrating the integrated Santa Rosa Plain Hydrologic Model to assess stream depletion and to simulate future climate and management scenarios in Santa Rosa, Sonoma County, California
The Santa Rosa Plain Hydrologic Model (SRPHM) was developed and published in 2014 through a collaboration between the U.S. Geological Survey (USGS) and Sonoma Water to analyze the hydrologic system in the Santa Rosa Plain watershed, help meet the increasing demand for fresh water, and prepare for future uncertainties in water resources. The original model simulated hydrological...